首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Synopsis. Facieplatycauda pratti gen. n., sp. n. and Myxobolus kozloffi sp. n., from the Klamath Lake sucker, Catostomus luxatus (Cope), are described. The new genus is placed in the family Myxobolidae between Henneguya and Myxobolus. The spore valves beyond the sporoplasmic space are broad and long but not attenuated as an inverted triangle as in certain species of Myxobolus with tails, or of Henneguya with sometimes bifurcated tails. An organism resembling Myxobolus insidiosus (Wyatt & Pratt) was found in the muscle of the body of Salmo clarki (Richardson). Differences in spore structure and site of infection suggest this is a subspecies of the previous form which should be designated Myxobolus insidiosus clarki. A previously unreported species of Myxobolus from Cottus aleuticus (Gilbert) is also described.  相似文献   

2.
Myxobolus gayerae sp. n. and M. leuciscini González-Lanza & Alvarez-Pellitero, 1985 (Myxozoa: Myxobolidae) have been described and re-described from European chub Leuciscus cephalus L. from the Hungarian stretch of the river Danube. The ellipsoidal plasmodia of M. gayerae sp. n. were found in the mucosa of the intestinal wall, whereas the large, elongated plasmodia of M. leuciscini infected the afferent arteries of the gill filaments. The spores of M. gayerae sp. n. are relatively large, slightly oval and almost rectangular in shape. On the basis of spore morphology and 18S rDNA sequences, the most similar species was M. cycloides Gurley, 1893, but the 2 species differed in host and tissue tropism as well as in the size of the spores. The spores of M. leuciscini from L. cephalus, having no intercapsular appendix or occasionally a very small one, showed a high morphological similarity to spores collected from L. cephalus cabeda, Chondrostoma polylepis and Rutilus arcasi in Spain and described as M. leuciscini González-Lanza & Alvarez-Pellitero, 1985.  相似文献   

3.
Two new species of Myxozoa from the brain of the green knife fish Eigemannia virescens are described: Myxobolus inaequus sp. n. has an unusually large spore body and extremely unequal polar capsules, and Henneguya theca sp. n. has an attenuated spore encased in a sheath not previously described in other Myxozoa . Only spores of the two species were observed, and infections caused no obvious pathological changes in the brain.  相似文献   

4.
Two new species of Myxozoa from the brain of the green knife fish Eigemannia virescens are described: Myxobolus inaequus sp. n. has an unusually large spore body and extremely unequal polar capsules, and Henneguya theca sp. n. has an attenuated spore encased in a sheath not previously described in other Myxozoa. Only spores of the two species were observed, and infections caused no obvious pathological changes in the brain.  相似文献   

5.
Henneguya episclera sp. n. is described from the episclera of the eye of the pumpkinseed sunfish (Lepomis gibbosus). Mean spore dimensions (in micrometers) are: total length 62.6; spore length 21.7; spore thickness 8.0; spore breadth 8.7; tail lengths 37.1 and 40.9; polar capsule lengths 6.0 and 6.5; polar capsule breadths 2.7 and 3.0; polar capsule thickness 3.5; and vacuole 5 by 5.  相似文献   

6.
A loose ammonite from the Nubian Sandstone near Abu Darag, Eastern Desert, Egypt, is described asNubidites omarai n. g. n. sp. Since ammonites from the Nubian Sandstone (Carboniferous to Cretaceous) are extremely rare, the new form is of great importance. The specimen has been found in a Carboniferous section of the Sandstone, but since Jurassic and Cretaceous outcrops occur in the neighbourhood, also these ages have to be considered. An Upper Cretaceous age of the new genus, however, is suggested.  相似文献   

7.
Henneguya cartilaginis n. sp. (Myxozoa: Myxosporea) is described from wild masu salmon Oncorhynchus masou masou in Hokkaido, Japan. H. cartilaginis n. sp. produced white cysts, up to 3mm in size, in the head of masu salmon. Infected fish exhibited cranial protrusion due to the cysts. Spores (11.4 × 8.6μm) of H. cartilaginis n. sp. were egg-shaped with the posterior end more pointed and possessed two caudal appendages (34.2μm average length). Histological observations revealed that large plasmodia possessing fine fibrous pseudopodia on the surface developed in the head cartilage. H. cartilaginis n. sp. resembles H. cerebralis, which was described from the cranial cartilage of Kosogol grayling Thymallus nigrescens in Mongolia. However, they were distinguishable by spore morphology. Molecular analysis of the 18S rDNA sequences indicated that H. cartilaginis n. sp. was most closely related to Henneguya zschokkei, H. nuesslini and H. salminicola of salmonid fish, with genetic similarities of 95.3%, 95.1% and 93.9%, respectively. Based on these differences in spore morphology, molecular data, the site of infection and geographical distribution, the present species is considered to be a new species.  相似文献   

8.
Bahupaathra minuta sp. n. has been described. It is distinct fromB. samala in possessing smaller phialospores and spore balls.  相似文献   

9.
During a survey on fishes from the River Danube, the occurrence of 8 Myxobolus species (Myxozoa: Myxobolidae) was registered in chub Leuciscus cephalus L. Most species had a specific location within the fish host. M. cycloides was found in the wall of the swimbladder; the branched plasmodia of M. dujardini were located typically in the epithelium of the non-lamellar part of gill filaments; the plasmodia of M. ellipsoides infected fins between 2 fin rays; M. muelleri and Myxobolus sp. 2 formed large elongated plasmodia in the afferent gill artery of filaments, while the round cysts of M. muellericus sp. n. filled the capillary network of the gill lamellae. Intramuscular plasmodia of M. pseudodispar proved to be the most common, although large cysts of Myxobolus sp. 1 were also frequently found in the intestinal wall. Despite similarities of some species in spore morphology, 18S rDNA sequences showed clear differences between the species examined.  相似文献   

10.
Myxobolus myleus n. sp. is described from the gall-bladder of the freshwater fish Myleus rubripinnis collected near the city of Oriximiná in the Amazon System, Brazil. The spores obtained from the bile contained two equal symmetrical and smooth valves, each forming the spore wall. The spores were large, with a cone-like form, a semi spherical basal contour and measured (in μm) 19.3 ± 0.5 (n = 25) × 8.3 ± 0.5 (n = 25) × 4.0 ± 0.3 (n = 15). The apical end of the spores contained two elongate, equal and pointed conical polar capsules measuring 13.2 ± 0.4 μm (n = 25) in length and 3.0 ± 0.3 μm (n = 15) in width, each having a slightly tapering polar filament with 19 to 21 turns. The polar capsules were extended below at about 4/5 of the total length of the spores. The sporoplasm was binucleate and contained some sporoplasmosomes. All infected fish presented hypertrophy of the gall-bladder due to presence of the brownish parasite floating in the bile. In this paper we describe this new species of myxosporean based on light and ultrastructural observations, together with its associated pathology.  相似文献   

11.
Meloidogyne camelliae n.sp. on camellia (Camellia japonica) from Japan and M. querciana n.sp. on pin oak (Quercus palustris) from Virginia, USA, are described and illustrated. M. camelliae n.sp. is distingnishable from other species of the genus especially by its striking perineal pattern having heavy ropelike striae forming a squarish to rectangular outline with shoulders or projections, appearing sometimes ahnost starlike. M. querciana differs from other species by its characteristic perineal pattern round to oval in outline, sometimes with a low arch, and sunken vulva surrounded by a prominent obovate area devoid of striae. M. querciana shows some relationship to M. ovalis, but differs further fxom the latter by longer larvae, absence of annules on head of larvae, and rarity of males. Examination of specimens of M. camelliae n.sp. and M. querciana n.sp. with the scanning electron microscope confirmed observations made by optical microscopy and revealed diagnostic and other structures in greater detail. In greenhouse host tests, M. camelliae infected camellia heavily, showed moderate infection on oxalis, only a trace infection on tomato, and no infection on five other plants tested; and M. querciana attacked pin oak, red oak, and American chestnut heavily, but did not infect nine other test plants. In another test, pin oak seedlings did not become infected when heavily inoculated with and grown in the presence of two populations of M. incognita incognita and one of M. incognita acrita. The common names "camellia root-knot nematode" and "oak root-knot nematode" are respectively proposed for M. camelliae and M. querciana.  相似文献   

12.
Recent recognition that tintinnids are infected by dinophycean as well as syndinean parasites prompts taxonomic revision of dinoflagellate species that parasitize these ciliates. Long overlooked features of the type species Duboscquella tintinnicola are used to emend the genus and family Duboscquellidae, resulting in both taxa being moved from the Syndinea to the Dinophyceae. Syndinean species previously classified as Duboscquella are relocated to Euduboscquella n. gen., with Euduboscquella crenulata n. sp. as the type. As an endoparasitic species, E. crenulata shares with its congeners processes associated with intracellular development and sporogenesis, but differs from closely related species in nuclear and cortical morphology of the trophont, including a distinctively grooved shield (= episome) that imparts a crenulated appearance in optical section. In addition, E. crenulata produces three morphologically distinct spore types, two of which undergo syngamy to form a uninucleate zygote. The zygote undergoes successive division to produce four daughter cells of unequal size, but that resemble the nonmating spore type.  相似文献   

13.
Myxidium volitans sp. nov. (Myxozoa: Myxidiidae) parasitizing the hypertrophied green-brownish gallbladder of the teleost Dactylopterus volitans, collected in the Atlantic coast near Niterói, Brazil was described based on ultrastructural studies. The spores were fusiform, sometimes slightly crescent-shaped on average 21.7 ± 0.3 μm (mean ± standard deviation) (n = 50) long and 5.6 ± 0.4 μm (n = 30) wide. The spore wall was thin and smooth, comprising two equally-sized valves joined by a hardly visible sutural ridge. Spores containing two pyriform polar capsules (PC) (5.0 ± 0.4 × 2.3 ± 0.3 μm) (n = 30) are situated in each extremity of the spore. The PC wall was composed of hyaline layer (0.20-0.29 μm thick) and by a thin external granular layer. Each PC contains a polar filament (PF) with irregular arrangements that was projected from its apical region to the bases of PC and coiled laterally from bases to the tip of PC. Some regular striations and S-like structures in the periphery of the PFs with four-five irregular sections were observed. Based on the spore morphology, ultrastructural differences and the specificity of the host we describe this parasite as a new myxosporidian, named M. volitans sp. nov.  相似文献   

14.
15.
Kudoa monodactyli n. sp. is described from the somatic musculature of Monodactylus argenteus from several localities in southern Queensland, Australia. This is the first record of a myxozoan parasite from the family Monodactylidae. The spores typically have five polar capsules, making this species similar to the four other five-valved Kudoa species (K. neurophila, K. muscularis, K. shulmani, K. cutanea) that have been described to date. However, morphometric measurements particularly of spore length and width make the species from M. argenteus distinct from the other species. Comparison of the small subunit ribosomal DNA sequence of this species with its congeners for which sequence data are available, provides further evidence of novelty. Kudoa monodactyli n. sp. displays 38 (of 1,554) nucleotide differences compared with rDNA sequence of Kudoa neurophila, which on phylogenetic analysis places these species in clades exclusive of each other. Phylogenetic analyses also provide evidence that the number of valves per spore in this genus is an imperfect indicator of relatedness.  相似文献   

16.
Seven species are reported from Ecuador, South America, two of which, Mixibius ornatus and Diphascon (Adropion) onorei, are new to science. Mixibius ornatus n. sp. differs from Mixibius saracenus (Pilato 1973) and from M. fueginus Pilato & Binda 1997 by having a sculptured cuticle, broader claws, lunulae present, stylet supports inserted on the buccal tube in a more caudal position, and shorter placoids. Diphascon (A.) onorei n. sp. has an elongate pharyngeal bulb with small apophyses, three rod-shaped macroplacoids, a granular microplacoid, and septulum; claw bases enlarged, smooth (first three pairs of legs) or crenate (outer claws on the hind legs); a cuticular bar is present near the inner claws on the first three pairs of legs. Other species reported are Echiniscus aliquantillus Grigarick, Schuster & Nelson 1983; Minibiotus intermedius (Plate 1888); Macrobiotus coronatus De Barros 1942; Macrobiotus danielae Pilato, Binda, Napolitano & Moncada 2001, and Astatumen bartosi Weglarska 1959.  相似文献   

17.
The marine, mobile, peritrichous ciliate Urceolaria convexa n. sp., a harmless ectozoon on Anaitides mucosa (Oerstedt, 1843), is described from the coast of the Northsea near Büsum (FRG). It is characterized by its bellied lateral walls and the dome shaped peristome (name), which is clearly separated from the body. The adoral cilia describes slightly more than a full circle (400°) and extends nearly horizontally. The height of Urc. convexa n. sp. varies between 27 and 35 µm, the diameter between 32 and 56 µm, The macronucleus has roughly the form of the letter H.
Zoologisches Institut and Zoologisches Museum der Universität Hamburg, (Geschäftsführender Direktor: Prof. Dr. W. Villwock)  相似文献   

18.
Meloidogyne grahami n. sp. is described and illustrated from specimens on tobacco (Nicotiana tabacum) originally from Florence, South Carolina. Considered for several years to be only a race of M. ineognita, this new species readily attacks NC-95 tobacco, a variety with resistance to the M. incognita group that is common in the major U.S. tobacco-producing areas. M. grahami n. sp. is related most closely to the three subspecies of the M. incognita group but differs from all of them, especially in its distinctive perineal pattern and larger larvae (av. 421 μm, vs. 385 μm or less). Also, the dorsal esophageal gland orifice of females of M. grahami n. sp. is further from the base of the styler (5 μm) than in M. i. incognita and M. i. acrita. Comments are given on the distribution of this new species.  相似文献   

19.
Myxobolus spirosulcatus n. sp. (Myxosporea: Bivalvulida), infecting the cultured yellowtail Seriola quinqueradiata, is described. M. spirosulcatus n. sp. was found in the bile duct of yellowtails collected in the southern part of Japan during June 1990. The plasmodium of the new species has various shapes and contains a vegetative form plus maturing and mature spores. Mature spores, on average, measure 8.9 m in length, 7.8 m in width and 6.7 m in thickness. The unique morphological characteristics of the new species are spiral furrows in the peripheral part of the spore valves.  相似文献   

20.
Henneguya curimata n. sp. (Myxozoa, Myxobolidae) is described from the kidney of the teleost Curimata inormata collected in an estuarine region of the Amazon River, near Belém. Brazil. This myxosporean produces large cysts (0.6-1.2 mm in diam.) that represent plasmodia containing all life cycle stages, including spores. The spore body is ellipsoidal (approximately 16.6 microm in length and approximately 6.2 microm in width), and each valve presents a tapering tail (approximately 19.1 microm in length). These valves surround the binucleate sporoplasm cell and two ellipsoidal polar capsules located side-by-side at the same level, measuring 6.5 x 1.2 microm each and containing 10-11 coils of the polar filament. On the basis of its host specificity and on data collected by light and electron microscopy, the organism, H. curimata n. sp. is distinguished as a new species. The taxonomic affinities and morphological comparisons with other similar species of the same genus are discussed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号